This invention relates to information systems for automobiles.
In traditional automotive electronic systems, dedicated components are employed to control specific functions in the vehicle. These dedicated components are typically independent of one another, each with its own operator interface. For instance, most modern automobiles have an electronic engine control system, a computerized antilock braking system (ABS), a vehicle safety system, a lighting control system, a climate control subsystem, and a sound system. Most vehicles also have power door locks, power windows, and power seating for the operator""s comfort.
Some automobile models are equipped with a navigation system that employs a global positioning system (GPS) receiver to receive positioning signals from a satellite network. The navigation system computes coordinates that locate the vehicle over the surface of the earth with regard to longitude, latitude, and altitude. Cellular communication systems have also been introduced into automobiles to enable the driver or occupant to transact telephone calls from their vehicle. Most late model automobiles are also constructed with a diagnostic system that analyzes the performance of the automobile engine, air and heating system, and other components (1996 or later for OBD II, 1993 or later for OBD I).
While these various electronic control units have proven useful, there is a drawback in that all of them are entirely separate and independent from one another. Generally, different manufacturers supply these subsystems. These disparate components often employ proprietary, dedicated processors or ASICs (application specific integrated circuits) that have different system architectures and execute incompatible proprietary software. The components have limited or no communications with one another.
Yet, today""s automotive electronic systems increasingly encompass a broader range of functionality, such as task management, resource management, communication with other control units or systems, time-critical monitoring and control of equipment. This requires increased integration of components into networks of distributed and multiplexed electronic system, as well as interfaces for s communication between the control units and for communication with the operator. The motivations for this increased integration of the automotive electronic system are many, including:
Cost reduction of existing functions;
Cost effective improvement of existing functions;
Cost effective enabling of new functions;
Reduction of wiring weight;
Simplify addition of new functions via software upgrade;
Optimization of electronic and mechanical integration;
Increase of system performance, intelligence, and coherent; and
Increase data communications with external systems/infrastructure.
Some strides have been made to integrate the components. Typically, the proposals call for each of the distributed components to be connected to a data bus, such as a CAN (Controller Area Network) protocol bus. Designers have theorized different multiplexing protocols and token passing protocols to facilitate communication over the bus. For more information on these proposals, the reader is directed to the following articles which appear in a publication from the Society of Automotive Engineers (SAE): Inoue et al., xe2x80x9cMultiplex Systems for Automotive Integrated Control,xe2x80x9d Multiplex Technology Applications in Vehicle Electrical Systems, SP-954, No. 930002, copyright 1993; Azuma et al., xe2x80x9cDevelopment of a Class C Multiplex Control IC,xe2x80x9d Multiplex Technology Applications in Vehicle Electrical Systems, SP-954, No. 930003, copyright 1993; Mathony et al. xe2x80x9cNetwork Architecture for CAN,xe2x80x9d Multiplex Technology Applications in Vehicle Electrical Systems, SP-954, No. 930004, copyright 1993; Szydolowski, xe2x80x9cA Gateway for CAN Specification 2.0 Non-Passive Devices,xe2x80x9d Multiplex Technology Applications in Vehicle Electrical Systems, SP-954, No. 930005, copyright 1993; Neumann et al., xe2x80x9cOpen Systems and Interfaces for Distributed Electronics in Cars (OSEK),xe2x80x9d Automotive Multiplexing Technology, SP-1070, No. 950291, copyright 1995; and Emaus, xe2x80x9cAspects and Issues of Multiple Vehicle Networks,xe2x80x9d Automotive Multiplexing Technology, SP-1070, No. 950293, copyright 1995.
While there has been some progress at interconnecting electronic components in a distributed system via a communication link, there is no commonly accepted standard for the main vehicle system bus and bus interface. Achieving the above objectives entails a system design that is flexible and scaleable, with the capability to manage complex functions.
This invention concerns an automobile information system that facilitates communication within clusters of components and among various clusters. Each cluster has a controller that provides a platform for supporting many diverse components.
In one implementation, various automobile components are grouped into logical clusters. For example, components used to control an operator""s environment in the automobile (e.g., climate control, lighting, seat position, window placement, door locks, etc.) might form a first cluster. Another cluster might contain components related to entertainment and communication functions (e.g., audio, navigation, cellular communications, etc.).
Each cluster has its own cluster controller to manage information flow among the cluster""s components. A data communications bus interconnects the cluster controller and components. The cluster controller is responsible with disseminating information received from external sources to the various components with interest in the information as well as exchanging information between two or more components within the cluster.
Each cluster controller is implemented, for example, as a general-purpose computing device having an open platform operating system. The operating system offers a platform with APIs (application program interfaces) and DDIs (device driver interfaces) that allow developers to interface different peripheral components with a common controller. The cluster controller supports multiple applications and provides interfaces for those programs to the hardware peripheral devices. The cluster controllers are interconnected via another data communications bus to enable information flow between clusters. In this manner, any component in one cluster can share information with any component in another cluster without need for dedicated wiring or specially written code.